I have seen this problem over and over on the various magic screen
games that I own and have sold. I never gave it to much thought until
Doc Morrow asked me to fix one of his Lido games for a customer. This
particular Lido had fire damage that was caused by the reset coil on
the Sequence Unit burning up. The reset coil on the Winner Unit was
also burnt badly but didn't catch fire like the Sequence Unit coil
did.

The root cause was the problem I am going to describe in detail, the
timer stepped to the 8th step and shut the control motors off before
the register cycle had completed. The result was that control unit
switch 16A stayed closed keeping constant current on both the Sequence
and Winner Unit reset coils, followed by FIRE.

"Hey Jeff, this can't happen!" "The timer resets every time I press
the "R" Button, right?" Yes, it does. Now let me explain what causes
this "impossible" situation.

jeffrey lawton

location of switch 14B

The Timer Unit moves 8 total steps for a complete timing cycle. This
is controlled by operation of the Before 5th Ball Lock relay and three
control unit switches, SW 1A, the Drag Arm switch and SW 14B. SW 14B
is normally closed except during payout, SW 1A and the Drag Arm switch
close at random. When SW 14B, SW 1A and Drag Arm switch all close
simultaneously, the Timer Unit steps once.

"OK, so what's the big deal, SW 14B is open during the payout cycle,
right?" Wrong! It is open during ONLY PART of the payout cycle. SW
14B CLOSES each time the Replay Cams passes from position 12 through
index to position 1.

To solve this problem, move the leads off SW 1A and put an additional
switch on the stack on the outside of the Search Disc. This stack
contains switches that prevent the R Button and the Magic Screen
Buttons from activating during a register cycle.
This simple modification will prevent you from having a fire similar to the one I
am fixing for Doc Morrow.

I initially thought you could simply move
the wires off SW 14B but if you do that it is possible for the game to
miss the count pulse needed to advance the timer for 5th ball
detection so that won't work. SW 1A always works because it isn't
activated until after the 5th ball has been shot.

Note: using this method the motors will shut down very quickly after the
5th ball is shot - which is ok. If you want the original 1-2 minute delay, wire the
extra switch in the search wiper stack in series with switch 1A